The SM-501 Series Duct Smoke Detector provides early detection of smoke and products of combustion present in air moving through HVAC ducts in commercial, industrial and residential applications. The SM-501 is designed to prevent the re-circulation of smoke by the air handling systems, fans, and blowers. Complete systems may be shut down in the event of smoke detection.

The SM-501 model will operate on any one of four input voltages (230VAC, 115VAC, 24VAC or 24VDC). The SM-501 allows up to 30 detectors to be interconnected for many common functions.

The SM-501 is enclosed in a compact housing. Each unit provides two sets of 10 Amp form “C” alarm contacts, along with one set of 10 Amp form “C” trouble contacts for monitoring head removal and supply voltage failure.

The green pilot and red alarm visual indicators provided on the front of the SM-501 duct unit signal the operating status of the device. The green pilot LED will be extinguished when the detector head is removed. A manual test/reset switch is located next to the visual indicators.

The SM-501 has been specially designed to allow common detector functions to be linked between up to 30 detectors. Specifically, 30 units may be wired to use a common test/reset function, and to alarm when a single unit alarms. Also, up to 15 units with signaling devices may be interconnected to operate with a single alarm. The SM-501 is designed and built to meet all local requirements, as well as the NFPA regulations regarding duct smoke detectors. Output terminals are provided for remote accessories such as horns, strobes, remote status indicators and test/reset key switches or push buttons.

The ionization and photoelectric detector heads are interchangeable. Air sampling is accomplished via two tubes which protrude into the duct. An exhaust tube of one standard length (7.0") is supplied in the installation kit with the duct smoke unit. Once the duct width had been determined, the air intake sampling tubes must be ordered. Sampling tubes are supplied in three standard lengths (2.5ft, 5.0ft and 10.0ft), and are cut to size to fit the duct. Mounting the duct smoke detector is accomplished be the use of a template and four sheet metal screws, as provided. Mounting can be achieved without the removal of the clear cover, which is secured by four captive screws.

Standard Features:
• Operating voltages 230VAC, 115VA, 24VAC, 24VDC
• Interconnect up to 30 units for common functions
• UL, CSFM and MEA Listed
• Compact Size
• 2 Sets of alarm contacts
• 1 set of trouble contacts
• Rugged steel back box with clear cover
• Compatible with the WP-1 weatherproof enclosure
• Easy retro-fit/upgrade of existing RW Series detectors
• Clear cover fitted with 4 captive screws
• Large terminal connection screws
• Interchangeable “Plug-In” photoelectric or ionization heads
• Easy Installation without cover removal (Mechanical)
• Dust filtering in detector head
• No additional screens or filters to clean
• Over 15 remote accessories available